W925EP01 Datasheet, PDF (15/108 Pages) Winbond – 8-BIT CID MICROCONTROLLER

W925EP01/ W925EP01FG
P0: P0 can be selected as input or output mode by the P0IO register. At initial reset, P0IO is set to
FFH, P0 is used as input mode. When P0IO is set to 0, the P0 is used as CMOS open drain
mode.
STACK POINTER
(initial=07H)
Bit:
7
6
5
4
3
2
1
0
SP.7 SP.6 SP.5 SP.4 SP.3 SP.2 SP.1 SP.0
Mnemonic: SP
Address: 81h
SP: The Stack Pointer stores the scratchpad RAM address where the stack begins. In other words,
it always points to the top of the stack.
DATA POINTER LOW
(initial=00H)
Bit:
7
6
5
4
3
2
1
0
DPL.7 DPL.6 DPL.5 DPL.4 DPL.3 DPL.2 DPL.1 DPL.0
Mnemonic: DPL
Address: 82h
DPL: This is the low byte of the standard 8052 16-bit data pointer.
DATA POINTER HIGH
(initial=00H)
Bit:
7
6
5
4
3
2
1
0
DPH.7 DPH.6 DPH.5 DPH.4 DPH.3 DPH.2 DPH.1 DPH.0
Mnemonic: DPH
Address: 83h
DPH: This is the high byte of the standard 8052 16-bit data pointer.
DATA POINTER LOW1
(initial=00H)
Bit:
7
6
5
4
3
2
1
0
DPL1.7 DPL1.6 DPL1.5 DPL1.4 DPL1.3 DPL1.2 DPL1.1 DPL1.0
DPL1:
Mnemonic: DPL1
Address: 84h
This is the low byte of the new additional 16-bit data pointer. That has been added to the
W925EP01. The user can switch between DPL, DPH and DPL1, DPH1 simply by setting
register DPS.0 = 1. The instructions that use DPTR will now access DPL1 and DPH1 in
place of DPL and DPH. If they are not required, they used as conventional register locations
by the user.
DATA POINTER HIGH1
(initial=00H)
Bit:
7
6
5
4
3
2
1
0
DPH1.7 DPH1.6 DPH1.5 DPH1.4 DPH1.3 DPH1.2 DPH1.1 DPH1.0
Mnemonic: DPH1
Address: 85h
- 15 -
Publication Release Date: Apr. 10, 2006
Revision A2